1. Field of the Invention
The present invention relates to a device for overriding a time switch in a control circuit for an air conditioning system, and more particularly to such a device connected between an air conditioner unit and a thermostat control unit remote therefrom for overriding a timing switch adapted to inhibit operations of the unit at predetermined intervals, the device being actuatable from the thermostat without requiring the addition of a switch at the thermostat or additional wiring to the thermostat.
2. Description of the Prior Art
It is well known to provide air conditioning systems with a control circuit having a timing switch, hereinafter referred to as a time switch, adapted to inhibit operation of the system at predetermined hours. Such a system is typically utilized in an office building to interrupt and inhibit the operation of an air conditioner unit outside of the usual office hours, for example, between 5:30 p.m. and 7:30 a.m. and on Saturdays and Sundays. Such systems result in the substantial savings in energy, since the buildings are not heated or cooled when substantially unoccupied.
However, personnel working outside of usual business hours frequently are subjected to uncomfortable temperature conditions during the periods when operation of the system is interrupted. Even though it would, of course, be possible to obtain relief by resetting the time switches, such switches usually are made relatively inaccessible in order to prevent unauthorized changing of established operational time periods. Further, the resetting of such switches often involves complex manipulations.
It is known to provide a conventional air conditioning system thermostat unit, located in an air conditioned space, with a manually actuatable overrride switch or the like, for initiating operation of a timer. The purpose of such a switch is to override the time switch for a predetermined period, typically an hour. A longer override period may be obtained, as desired, by subsequent actuation of the switch toward the end of each predetermined period.
Often, an override switch is convenient to operate from the air conditioned space and its use with a timer avoids having to reset the time clock. However, the addition or coupling of such a switch in a thermostat control circuit requires the installation of the circuit wiring between the thermostat and an associated air conditioner unit. Such involves procedures which are relatively time consuming and expensive to complete, particularly where a time clock is to be retrofitted in a building having an air conditioning system not originally provided with this energy saving feature.
It is, therefore, highly desirable to provide a selectively operable device adapted to override for a predetermined period a time switch for interrupting and inhibiting operation of an air conditioner unit at predetermined hours, the device being actuatable from an existing thermostat remotely related to the unit, without modification of the thermostat and without requiring that additional wiring be strung between the thermostat and the unit.